Kate's car was stationary at the time of taking the picture. But still, she's apologised after being blasted by safety campaigners for taking a picture from behind the wheel of her car while taking her son to school.

Kate posted the photo on Twitter last week, saying: 'Ah school run traffic how I've missed you'.

Yesterday, she said on twitter: 'I hope my mistake ultimately raises awareness and saves even one accident from happening. Thank you @Brakecharity for raising my awareness. Had no idea taking a photo on my phone whilst at stand still in car was illegal.'